<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        .con {
            /*color: red;*/
            color: #ff0000;
            /*rgb  ff 00  00 

                 255 0 0*/
            /*color: rgb(99, 217, 253);*/
        }
    </style>
</head>

<body>

    <div class="con">

        哈哈哈哈哈哈哈

    </div>

</body>

</html>